Multiple band blade slicing machine



oct. 27, 1942.

W. W. HARTMAN MULTIPLE BAND BLADE sLIcING MACHINE' Filed May 25, 1940 4 sheets-sheet 1 g1 l WMM@ .HitIn/ways.

Oct. 27, 1942. w. w. HARTMAN 2,300,278

MULTIPLE BAND BLADE SLICING MACHINE y Filed May 25,4940 44 sheets-sheet 2 In ven Zar. WllamVaZterHa/'I/nan.

2. I '.orneys.

Oct. 27, 1942.

w. w. HARTMAN 2,300,278 MULTIPLE BAND BLADE sLlCING MACHINE Filed May 25, 1940 4 Sheets-Sheet 5 Q y lf-Ivv e 43 l l l W ig /7 4/ 2:: f 40 :l j fix.. ,e'

l u II//l ,f am g 2 *i l/zz/ezar:

' William Waler Har/nan.

@MJ MM5 .Horne Oct. 27, 1942. \w. w. HARTMAN MULTIPLE BAND BLADE SLICING MACHINE` Fild May 25, 1940 4 Sheets-Sheet 4 L In Ue/z fol: William WaILer/Ya/-Zmam Patente-d Oct. 27, 1942 UNETED STATES PATENT OFFICE e 2,300,278 Y MULTIPLE BAND BLADE SLIACING MACHINE William Walter Hartman, Los Angeles, Calif.

Application May 23, 1940, Serial'No. 336,842

6 Claims. (C1. 146--88) This invention relates generally to machines for slicing articles, such as loaves of bread, and more particularly to slicing machines of the multiple endless band blade type.

It has for some time been the considered weight of opinion among those skilled in the art to which the present invention appertains, that proper tensioning of the blades of a multiple band blade machine necessitates individual means for tensioning each blade. This practice has been followed partly from the fact that individual band blades as heretofore manufactured have-varied in length to a substantial degree, and partly, perhaps, by the belief that the blades were being taxed beyond their elastic limits under service conditions, and that blade lengthening over a period of time was a factor necessary to be cornpensated. More recently, however, it has been ascertained that with due care in manufacture, blades of very uniform length can be produced, and careful investigation has also revealed that the blades are not actually or necessarily stretched beyond their elastic limits in service. Accordingly, by exercising a high degree of care to see that all the blades to be used on a given machine do not depart from a predetermined length by more than a given tolerance, it is possible to tension all the blades at once by exerting tensioning pressure on a single drum about which all the blades run. A safe tolerance is, for instance not more than .001" for each foot of blade length.

A primary object of the invention accordingly may be stated to be to provide an improved multiple band blade slicing machine in which all of the blades are tensioned by novel and improved means for exerting tensioning pressure on a single drum about or against which all the blades run.

A further object of the invention is the provision of novel and improved means for exerting blade tensioning pressure on a blade supporting drum of a band blade slicing machine, in conjunction with novel and improved means for facilitating the mounting of the blades kon the blade supporting drums of the machine.

The present invention is here illustrated in the form of a band blade slicing machine of the twodrum, figure-8 type, and while certain features of the invention have to do particularly with the figure-8 type of machine, and are particularly applicable to that type of machine, in broader aspects the invention is not to be considered as restricted to figure-3 machines, and the claims appended to the present specification are accord- 55 3-3 of Fig. 2

ingly not to be consideredaslimited to thefigure B type of machine unless expressly s o stated.

In accordance with the present invention, a drum about or against which all of the blades of the machine run is provided at each of its ends with mounting means including aspring element whichurges the drum to move in a direction to tension the blades. Means are4 provided for stressing these springs to exert a predetermined pressure on this blade tensioning drum, and these spring-stressing means arel always setV up to a fixed limiting position at which an accurately predetermined pressure is exerted, but beyond which further travel is impossible by reason of the provision of certain engagingstop elements, so that this predetermined pressure cannot be exceeded. It is importantv that the pressure so exerted on the drum be limited to a proper predetermined working value, both from the standpoint of yavoidingover-stressing of the blades, and from ythe standpoint of avoiding stressing the bearings for the several drum shaftsbeyond the point for which they were designed. Arrangements are further provided for withdrawing the springstressingmeans to relax the pressure exertedl by the springs, thereby bringing about suiiicient retraction of the blade ytensioning drumto permit' installing or removing blades. When the means for stressing the springs are then re-set, the pressure exerted on the drum goes back precisely to, and cannot exceed, the value accurately predetermined in thefactory,` and there is positive assurance that the blades will not be overstressed, and the bearings for the drum shafts will not be over-taxed.

The present application is a continuation, in part, of my copending prior application. entitled Multiple band blade slicing machine, Ser. No. 249,047,1iled January 3,1939, and which became Patent No. 2,205,527 on June 25, 1940, thepresent application disclosingand claiming certain subject, matterof invention disclosed but not claimed in the aforementioned parent application.

Various additional objects and features of the invention will appear and. be fully described in the course ofthe following detailed description of a present illustrative embodiment thereof, reference for this purpose being directed tothe accompanying drawings, in which:

Fig. 1 is a side elevation of a slicing machine in accordancewith the presentinvention;

Fig. 2 is a section taken on linesV 2-2 of Figs. 1 and 3;' A f Fig. 3 isy ay section taken` as indicatedv by line While the present invention may be regarded as particularly applicable and adaptable to what is commonly referred to as the figure-8 type i.

of slicing machine, and is here illustrated as incorporated in such a machine, itis nevertheless to be understood that various features of the invention are applicable also to other types of band blade machines, and no limitation to any particular type -of machine is-therefore to be inferred, except where expressly so indicated.

With-this understanding, reference-is now directed to the4 drawings, 4in Ywhich the Villustrative slicing machine is'desig'nated generally by numeral I 5. The general frame structure of the machine includes a base II, upon which' is mounted a vertically elongated rectangular frame or housing-structure I2 surmounted by a top I3. Mounted on base I| and extending upwardly to top |3, at one side of the machine, is a channel member |4 which constitutes a part of the -stationary frame, and on which certain operative parts of the machine are mounted, as later to be described. In the present channel member is disposed at somewhat of an angle with reference to vertical, such as indicated in Fig. 1, which results in a certain convenient disposition of the various members of the machine, and also in a desirable downward inclination for the path of the loaves as they are passed through the cutting blades. It will be understood, however, that the particular disposition of the channel member I4, andv of the parts mounted thereon, with reference to vertical, is open to considerable modification, and that no limitation is to be implied from the lparticular disposition.

drums 2| and 22, respectively, which preferably and as here illustrated are of the same diameter and havetheir axes substantially parallel. Each blade goes on drums 2| 'and 22 in ligure-8 form,

instance, this with the upper blade loop being passed over upl each band blade to a position where they cross P one another and where they are directed toward the front end of the machine, from which direction the` loavesl or other articles to be sliced are fed against the blades. .'i

Lower drum 22 is revolubly mounted on a nonrotatable shaft 23, one end of which is tightly fitted within a mounting 24 secured to the lower end portion of the aforementioned channel mem ber I4, in the manner clearly illustrated in Fig. 2. Drum 22 comprises a cylindrical shell 25 mounted on drum ends 26 and 21, which are mounted for rotation, as by means of bearings 21a, on the aforementioned fixed shaft 23. The entire weight of the drum may thus be supported by the one xed end of shaft 23. A removable support is provided for the other end of .haft 23. Thus, as here typically shown, said end of the shaft has a conical socket 28 adapted to be engaged by the pointed end 29 of a supporting screw A3|) screwthreadedly mounted in a mounting block 3| secured to base II. The inner side of mounting block 3| is spaced somewhat from the outer end of drum 22, so as to give a clear-I ance space, when the screw 30 is retracted, throughl which the' blades may be passedinthe operation of looping theml over the lower drum during assembly.

The end of drum 22 adjacent channel member |4 is formed with apair of peripheral V-grooves 33 for driving V-belts 34, which are driven by pulley 35, powered through suitable reduction gearing, not shown, from the shaft of an electric motor 36 mounted on base I Y Upper drum 2| comprises a cylindrical shell 45 mounted on apair of drum ends 4|, which are revolubly mounted through bearings 42 on a non-rotatable shaft 43. -The end of shaft 43 adjacent channel member I4 is tightly mounted within a hub 44 formed at the upper end of va slide member 4", the edge portions of which are received and guided within a way providedY by jib plates 46 secured to channel member I4 as by means of screws 41 (see Figs. 4 and 5). The member 45 comprises the supporting member for the corresponding end of drum shaft 43, and is in turn supported through spring means as presently to be described. g

The way defined bythe jib plates 43 extends in the direction of the plane defined by the axes of drums 2| and 22, and itwill be apparent that movement of member 45 upwardly or downwardly in said way tensions or de-tensions the blades as the case may be. e i

Member 4'5'has at the bottom a wall or abutment 50, which engages and is supported by the upper end of a compression spring 5|, thelower end of which seats on a spring supporting ele-- ment 52, her'efshown in the form of a centrally perforated disk. This spring supporting element 52l restson the upper end of a lead screw 53, which coacts with and works'through an internally screwthreadedbevel gear55. The lower end of the latter restsl through thrust bearing 5S on a 'bracket 5l' mounted on channel member i4. Thus, the downward pressure sustained by drum supporting member 45 is transferred via sp1-ing 5I', spring supportingelement 52, lead screw 53 and bevel gear 55 to bracket 5l mounted ony channel member- I4 which is a part of the fixed frame. Lead screw 53 is-prevented from turning by means of a key, here in theform of a screw 58, engaging in a longitudinal spline-way 51%,H lscrew 58 being mounted in a bracket member 65 `secured to channel member I4; v VBevel gear 55 is turned by means of a meshing bevel gear 62 on u the 'inner'endf of a shaft v63 turning in al bearing 64 mounted onchannel member I4 (see Fig.2),v the other en'd of said` shaft63 having thereon'a 'hexagonal' head |55 4adapted to be engaged and rotated by means of a crank G or any other suitable means.

Rotation of gears B2 and 55 by means of` crank causes lead screw 53 to be elevated or lowered. Elevation of lead screw 53 is limited by means of a stop nut T) secured as by pin "ma on the lower end of the lead screw and adapted to engage the lower side of bracket 57 when the lead screw reaches a predetermined elevation. A tension rod 'Il having a head l2 on its upper end extends downwardly through an -aperture T3 in wall 59, longitudinally through spring 5l, through element 52, and is screwthreaded into the upper end of lead screw 53, as clearly illustrated in Fig. 4. The purpose of this tension member will be de scribed at a later point in the specification.

The opposite end of upper drum shaft 43 is supported, when the machine is in operation, by means of a mounting preferably in the form of a pivoted hanger '55, here shown as pivotally mounted on a pivot pin 'il carried by a mounting` member 18 secured to frame top i3 as by means of screw 79 (Figs. 2 and 6).

The hanger, in the particular form here illustrated, comprises a tubular body 86, having at its upper end an upper head 8l mounted on pivot pin TI, as illustrated in Fig. 6.v Tubular body f8@ has just below head Si an aperture 82 adapted to receive, with clearance, the reduced and tapered` end portion 83 of shaft d3, the flattened under'- side Eli of the latter bearing downwardly on a shaft supporting element cr disk 85 movable 1ongitudinally inside tubular body 8B. Disk 35 rests on the upper end of a compression spring 85, the

lower end or which seats on a spring supporting 1 element 87 here shown in the form of a centrally perforated disk, likewise movable longitudinally within tubular bodyS. Spring supporting element 81 is engaged by the upper end of a screw member 88, screw-threaded within a lower head or plug 89 screwed to a fixed position within the lower end of tubular body te. A stop nut Se, secured to screw 88, as by means of pin QI, engages head 89 to limit the travel of screw 8S upwardly within body 35.

A tension rod d3 screwthreaded at its upper end into shaft supporting e-lement 85 extends longitudinally through spring S5 and through an aperture 94 in spring supporting element S1, its lower end portion being received within a socket 55 in the end of screw 8S. A rounded nut 95 screwed onto the lower end of rod S3 is tightly mounted in a predetermined position thereon and is indicated in dotted lines in Fig. 2, enabling 'the blade loops to be passed on over the vend of the upper drum. 4To permit the'blades to bethus placed on the drum, however, the drum must be4 lowered somewhat, and this is. accomplished by lowering lead screw 53 by means of crank 6.6. As this is done, stop nutl separates vfrom bracketk 51 and tension rod head engages wall 54),.after which drum shaft lsupporting member 45 lowers with lead screw 53. rIhis lowering operation is carried on until the blades will go on .easilyover the drum.

When the spring supporting means are: set up to the operating positions illustrated Vin Figs. 4 and 6, withthe stop nuts 'iii and '95 abutting their respective stops,y the two supporting springs 5l and B5 are under a predetermined compression. This compression is predetermined in the loosely received inside socket @5, nut 98 being so l located on rod S3 that there is a predetermined spacing distance between its upper end and the lower face 0f spring supporting element 3l when spring 85 is compressed (Fig. 6). Nut S5 may be secured in position as by means of a securing pin 95a. The end of the drum shaft thus rests on supporting element B5, and the downward pressure exerted thereby is transferred through spring 86, spring supporting element 87, screw 88 and head 8S to the body 5i! of the hanger 75 suspended from the fixed frame.

W'hen blades are installed in the machine, the

screw 85 is backed down, allowing the spring 85 Hanger 16 maythen be swung outto the position 75 -88 in that position.

factory at a value such as will assure proper tensioning of the blades by the drum 2l, which is pressed in an upward direction bysaid springs, Vbut such as will avoid-.overstressing the blades and also the bearings and supporting provisions for the drums and drum shaftsi l.

The predetermined compression of the springs is established as follows. For example, prior to assembly of the part's'comprising hanger "It, the members and 8l, with the spring 86 therebetween, are-forced toward vone another, asin-a vise, against the pressure of the spring, to apredetermined compression. This compression will of course vary with the design ofthe machine, but it will amount usually to several hundred pounds. While the springf is accurately held under lthis compression which has been determined as proper, the nut 955'r is then screwed onto tension rod 93'to.a position such that there is a predetermined gap between vits upper end and the adjacent face of memberl 87, which gap may be for example 1%. The compression is then relieved, allowing. member 81 to engage nut 96. The spring assembly, thenin the condition illustrated in Fig. 7, is then inserted within the tubular hanger body BEL head 8S is screwed in place, and `screw 8'8 is advanced yuntil member 87 is eng-aged and is moved upwardly until the l/f` gap between the upper end of nut 96 .and the adjacent face of member 37 is reestablished. .Nut 9i) is then screwed upwardly onscrew 88 until `it engages head '89, and is then pinned on screw The device is 4then in the condition of Fig. V6, land the spring 85 is under the same compression as it was when inthe vise. Now, whenever screw 88 is subsequently backed away, for the purpose of releasing the supporting pressure against the underside of shaft end 83, and is then reset, `it is always screwed back up until nut 9i! engages head 89. The predetermined compression -of spring 85 is therebyaacelv curately reestablished;l

An exactly similar procedure is ffolloweddn establishing the compression of spring 5i. "I'hus spring 5| is rst assembled with member d5, mem- Y ber`52, tension Irod 'H and leadscrew 53, Members 4'5 and 52 are then 'clamp-ed, as in a vise, andthe spring v5i compressed to the predetermined compressionvalu'e. r Tension rod 'll is then adjusted until there is a predetermined gap be'- tween its head 'I2 Yandi-the wall 5t.' This gap will be the sa-me as that provided between themem- `ber 8.1 and nut of the other'l'spring assembly, and |may'thus be 1/3"'. The assembly is then re'- moved from the vise, the spring `5l being allowed to expand to the limit imposed by the engagement of. wall 50 with .tension rod vhead l2.' The device is then assembled in theslicing machine', the blades are mounted on the drums, and the lead screw 53 is advanced or elevated until the head 12 of the tension rod 1I has become el-evated above the wall 50 of drum shaft supporting member 45 (which is being helddown by the blades) by the above mentioned predetermined spacing distance or gap. The nut 10 on lead screw 53 is -then set up against bracket 51 and pinned fast to screw 53 in that position. The

at proper tension, and henceiare not liable tostretching in service; moreover, rover-strain on the drum mountings suchas might result from over-tensioning the blades is.prevented.`

In order to complete the disclosure of an operative slicing machine, typical blade twisting guide means, loaf infeed means, and certain other adjuncts will be described, .though these parts per se do not form a part of the present invention.

Along the blade courses between the drums, I provide spaced-apart blade-twisting guide means, which can take variousforms, one form being illustrated by the parallel, notched plates I I5 and Thes-e plates are spaced apart to form between them a slicing zone for the blades, and through this slicing zone Ithe Vloaves or other articles to be sliced are fed. Infthis 'slicing zone the blades run in spaced parallel slicing planes, having been twisted into such planes by the guide grooves or notches in plates |'|0 and III. Thus these plates I IIJ and l, supported as later to be described, are provided with rows of `alined blade twisting guide slots IIa and I||a, respectively, f

adapted to receive the individual courses of the band blades and space them apart according to the .slice thickness required. i As will 4appear from the drawings, the downwardly and upwardly travelling courses of each band blade are received in adjacent guide slots of these plates Il and III, in such manner that each blade course makes a 90 twist between each guide plate and the drum from which, or onto which, that blade course is travelling.

Between guide plates IIB 'and,|||, the blade courses are disposed in spaced parallel slicing planes. The two courses of each bla'de cross one another at an angle dependent upon the diameters of the drums and the distance between drum centers. In general, lfor reasons well understood in the art, it is desirable that this angle be as small as possible.

The lower guide plate III is shown provided with down-turned flanges or brackets I2|l, by which it is secured to a transversely extending flange member I 2| which extends downwardly from the forward edge of a horizontal feed table |22, the latter, which is flushwith the upper surface of guide plate III, being supported-in the machine frame in any suitable manner,A -In order to accommodate loaves of different sizes, it is desirable that upper guide plate IIO be vertically adjustable. In the illustrative Aconstruction here shown, plate is mounted 'on the 75 forward portion of a loaf hold-down plate |24, which is in turn mounted, by means of brackets 25, on the lower end of a pair of vertically movable racks |26. The lower surfaces of plates and |24 are flush, and together form an upper guide and hold-down plate for the loaves.

Racks |26 extend through guideways |2611 formed in bearing mountings |21 secured to a transverse plate or bar |28. One end of this transverse bar |28 abuts and is welded to the Aupper portion |360. of a frame member or bracket |30 secured to and extending from the left hand angle member I as viewed in the aspect of Fig. l. The other end of bar |28 is supported by a bracket |28al extending from the left-hand vertical angle member I5 as viewed in Fig. 3.

A h'orizontal, transversely extending shaft |32 is journaled in bearing mountings |21, and has gear teeth I 33 meshing with racks |26 (Fig, 9). Rotation of this shaft |32 causes vertical movement travel of racks |26, and therefore adjustment of plates and |24.

One end of shaft |32, here the end corresponding to channel member I4, is provided with a hand wheel |4I, the shaft being shown as projecting through an aperture |42 in channel member I4 and hand wheel |4| being positioned outside said channel member, where it can be conveniently reached when the corresponding side door of the machine is opened. Mounted on shaft |32 between channel I4 and bracket |30 is aratchet wheel |43, and an arm |44 pivotally mounted on the side of frame member |a, as at |44a, is provided with a dog |45 adapted to engage between the teeth of ratchet wheel |43 to hold said ratchet wheel, and therefore shaft |32 on which the ratchet wheel is tightly mounted, against rotation. When it is desired to effect vertical adjustment of blade guide plate I lil and loaf hold-down plate |24, arm |44 is lifted to disengage dog |45 from ratchet wheel |43, permitting shaft |32 to be rotated by means of hand wheel I4 When the adjustment has been accomplished, arm |44 is lowered to reengage dog |45 with the ratchet wheel.

The loaf feeding means, for advancing the loaves through the slicing means, forms no part of the present invention, and any suitable or desired means for accomplishing thispurpose may be provided. However, while any suitable loaf feeding means may be provided, I have, for the sake of completeness, indicated one simple illustrative type of loaf feeding means involving a reciprocating ram |60, operated through crank pin |S| and pivoted, slotted arm |62, and a gravity feed chute |65. It will be readily understood, without detailed explanation, `how the loaves may travel down feed chute to a position on feed table |22, forwardly of ram |60, and how said ram will engage and advance the loaf s0 deposited before it, forwardly along feed table |22, and finally between blade guide plates IIII and III and so through and clear of the blades. To prevent the succeeding loaf from lowering until the ram has been retracted, the ram is equipped with a rearwardly extending tail plate |66 which supports said succeeding loaf until the ram has been substantially fully retracted, as will be readily understood. This type of feeding mechanism is well known in the art and will require no further explanation.

Any suitable or conventional type of end guides for the loaves while being sliced may be provided. End guides vfor this purpose are indicated by numerals |68 and |69 in Fig. 2.l

The loaves having been advanced through the slicing zone and clear of the blades, are received by any suitable means for conveying them from the slicer; I here typically and somewhat diagrammatically .indicate for this purpose a downwardly inclined plate or table |10. It will be understood however1 that any suitable out-feed provisions may be employed, Vthe details of which form no part of the present invention, and will therefore not require detailed illustration.

Preferably, for the purpose of backing up the blade courses at or near the slicing zone, and so that the blade courses will not be substantially deflected bythe pressure of the loaves, I employ transversely' extending blade backing-up rollers I'i2 and |73, the former being mounted somewhat above blade guide plate H0, so as to engage one set of blade courses, and the latter being mounted just below lower blade guide plate Ii l,.so as to engage and back-up the other set of blade courses. These long blade backing-up rollers are rotatably mounted in any suitable manner on shafts il@ and H5, the latter being supported at one end as by means of mountings HB and I7?, respectively, projecting from frame members l5, and at the other end by brackets, such as H8 and H9, projecting from frame member 13G.

I have now disclosed a multiple band blade slicing machine characterized by extreme simplicity of construction, assurance of proper tensioning pressure on all the blades, and characterized by positive assurance that neither the blades themselves nor the drum mountings will be over-stressed in service.

While I have now described and illustrated a present preferred embodiment of the invention. it will be understood this is for illustrative purposes only, and that various changes in design, structure and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

l. In a multiple band blade slicing machine embodying a stationary frame, a band blade drum against which run a multiplicity of endless band blades, a drum shaft on which said drum is revolubly mounted, the combination of mounting means for said drum shaft at one of its ends embodying a shaft supporting member tightly embracing the shaft end, means on said frame guiding said shaft supporting member for travel in a direction to increase the pressure exerted by the drum on said band blades, a spring supporting said shaft supporting member, and supporting means for said spring supported by said frame and adapted to be advanced with reference to said frame to a fixed operating position in which said spring exerts a predetermined pressure on said drum shaft supporting member, mounting means for the other end of said drum shaft embodying a mounting member connected with said frame and a shaft supporting member for said other end of said drum shaft associated with said mounting member, said mounting means being supported by said frame normally in a position withy said shaft supporting member in supporting engagement with said other end of said drum shaft, but movable with reference to said frame in a manner to separate its shaft supporting member from the drum shaft end, said shaft supporting member being movable, when in a position of supporting engagement with the drum shaft end, relatively to said mounting member in a direction parallel to the travel ofV the. supporting member for the first mentioned endy of the drum shaft, a yspring 4associated with said mounting member adapted to support said shaft supporting member for said other end of said' drum shaft, and supporting means for said spring mounted on said mounting member and movablethereon to and from a'xed operating position in which said springexerts a predetermined pressure on the shaftsupporting member which it supports.

2. In a multiple band blade slicing machine embodying a stationary frame, a band blade drum against which run a multiplicity of 'endless hand blades, a drum shaft on which said drum is revolubly mounted, the combination of mounting means for said drum shaft lat'one of its ends embodying a shaft supporting member tightly embracing the shaft end, means on said frame guiding said shaft supporting member for travel in a direction to increase the pressure exerted by thedrum on said band blades, a spring supporting said shaft supporting member, and supporting means forl said spring supported by said frameand adapted to be advanced with reference to said frame to a fixed operating rposition in which said spring exerts a predetermined pressure en said drum shaft'supporting member, a 'hanger for the support of the other end of the drum shaft pivotally connected with said frame, a 'shaft supporting member for said other end of said drum shaft associated with and carried by said hanger, said hanger being supported by said frame normally in a position with said shaft supporting member inv supporting engagement with said other endof said drum shaft, but movadapted to support said shaft supporting mem-r ber for said other end of said drum shaft, and supporting means for said spring mounted on said hanger and movable thereon to and from a fixed operating position in which said spring exerts a predetermined pressure on the shaft supporting member which it supports.

3. In a multiple band blade slicing machine embodying a stationary frame, a band blade.

drum against which` run a multiplicity of endless band blades, a drum shaft on which said drum is revolubly mounted, mounting means for one end of said drum shaft embodying a hanger pivotally connected with said stationary frame and a shaft supporting element forsaid shaft end associated with said hanger for movement toward and from the pivot of said hanger, said hanger being supported by said frame normally in a position with said shaft supporting element in engagement with said drum shaft end, but movable with reference to said frame in a manner to separate said shaft supporting element from the drum shaft end, a spring associated with said hanger supporting said shaft supporting element, and supporting means for said spring mounted on said hanger and movable thereon to and from a predetermined operating position in which the spring exerts a predetermined pressure on the drum shaft end. v

4. In a multiple band blade slicing machine embodying a stationary frame, a band blade drum against which run a multiplicity of endless band blades, a drum shaft on which said drum is mounted, and mounting means for said drum shaft at each of its ends, each of which comprises the combination of a pair of spaced members and a compression spring acting therebetween, a tension member extending between and limiting the separation of said spaced members to a given spacing distance, one of said members being adapted to support the corresponding end of the drum shaft, and means acting between the other of said spaced members and said iixed frame and movable against the opposition of said spring to a predetermined position to reduce the said spacing distance between said members by a predetermined amount,

whereby a predetermined supporting pressure is exerted by said spring against said drum shaft end.

5. In a multiple band blade slicing machinev embodying a frame, a band blade drum against which run a multiplicity of endless band blades, and a Vdrum shaft for said drum, supporting means for an end of said shaft embodying the combination of a pair of spaced members and a compression spring acting therebetween, means associated with said pair of spaced members and adapted to act in tension against said spring to limit the separation of said members to a predetermined spacing distance, one of said members being adapted to support said end of said drum shaft, and means acting between the other of said spaced members and said frame and movable against the opposition of said spring to a predetermined position to reduce the spacing distance between said members by a predetermined amount, whereby a predetermined supporting pressure is exerted by said spring against said drum shaft end.

6. In a multiple band blade slicing machine embodying a band blade drum against which run a multiplicity of endless band blades, a drum shaft on which said drum is mounted, and mounting means for said drum shaft at each of its ends, each of which embodies a guide for guiding the drum shaft end for movement in a direction to tension and de-tension the blades, a compression spring supporting said drum shaft end and urging it to move in a direction to tension the blades, and adjusting and supporting means for said spring movable to and retractable from a predetermined pressure limiting operating position in which said spring resiliently supports said drum shaft end with a predetermined limited blade tensioning pressure, said spring adjusting and supporting means including an axially adjustable screw, a stop shoulder on said screw, and a fixed stop engageable by said stop shoulder on said screw when said screw has been set up to said predetermined pressure limiting operating position, the stop shoulders on the screws of the two drum shaft mounting means always being in engagement with their respective fixed stops when the slicing machine is in normal operating condition, so as to denitely establish the blade tensioning pressure exerted on the drum shaft ends exactly at said predetermined limited pressure and thereby set the tension of lthe blades at a corresponding fixed predetermined tension.

W'ILLIAM WALTER HARTMAN. 

